Recently, efforts aiming to a reduction in energy consumption have been regarded as important. From such background, a Light-emitting Diode (LED) whose power consumption is comparatively small attracts attention as a next-generation light source. The LED features downsizing, small amount of heat generation, and good responsiveness. In view of this, the LED has been widely used as a display device, for example, for indoor, for outdoor, for stationary, and for movement; and an optical device such as an indicator lamp, various kinds of switches, a signal device, and a general illumination.
A wire bonding method has been conventionally used to mount this kind of LED to a wiring board. However, the wire bonding method is not suitable for mounting a LED chip to a flexible material such as a flexible substrate. Therefore, techniques for mounting the LED chip without the use of the wire bonding method have been variously proposed.
In a conventional module, the LED chip is disposed between one set of light transmissive films where light transmissive electrodes are formed. This kind of module is required to efficiently supply electric power to the LED chip while securing light transmissive property and flexibility of the module.
This kind of module is required to include a conductor pattern on the light transmissive substrate without sacrificing light transmissive property. However, when the plurality of conductor patterns are disposed on the substrate, a light transmittance at regions between the conductor patterns differs from a light transmittance at regions where the conductor patterns are formed. In view of this, depending on a shape and a positional relationship of the conductor patterns, the light transmittance possibly varies in the entire module. Especially, in the case where the plurality of conductor patterns are gaplessly disposed on the substrate, lines along outer edges of the conductor patterns stand out, also losing limpidity in appearance.